With the social credit system, the Chinese government gives citizens not only ratings based on criminal and financial crimes, but also on what they buy and say.
People who have low grades will get punished and their actions will be limited. China plans to launch the perfect version of this system by 2020. However, early versions of the system are already in use today.
Prior to this, the Chinese government focused on banning people with large debts - such as LeEco and Faraday Future founders, Yueting Jia travel. Jia broke into the blacklist of the Supreme People's Court last year.
In addition to debt, there are many other things that make a person marked by the government. People who distribute "misinformation about terrorism", causing problems with flights, using tickets that have expired or are caught smoking in trains may be prohibited from buying tickets.
Unfortunately, the Chinese government is not transparent with this system. Communities may be flagged for minor problems such as parking a bicycle on the sidewalk or apologizing insincerely.